WHAT IS BATHYBIUS? 
355 
son have conducted a very important series of deep-sea dredg- 
ings off the north coasts of Scotland, and in the neighbourhood 
of the Faroe Islands. In Captain Dayman’s dredging opera- 
tions the viscid mud was found between the fifteenth and forty- 
fifth degrees of W. longitude. Those of Drs. Carpenter and 
Thompson were carried on much further eastward ; but in the 
latter instance the same deposit was found over a range of at 
least 200 miles, throughout which the dredge came up from 
time to time filled with Globigerina-mud and saturated with 
Bathybium, with its associated Coccoliths and Coccospheres. The 
Globigerina deposit exists in a similar manner in many and distant 
parts of the ocean, in both hemispheres ; and it is more than pro- 
bable that when the remote localities are subjected to the same 
examination as our northern seas have recently undergone, 
Bathybius will be found in them also. Its low organisation 
renders it probable that it will be found to be like its com- 
panion Globigerina, a thorough cosmopolite. On this point Dr. 
Carpenter suggests that the range of these objects is regulated 
by temperature rather than by locality. It was already known 
that many deep-sea localities existed, in which the Grlobigerina- 
mud did not occur; and it had even been suggested that its 
range was limited to that of the warm Gulf-stream. Dr. Car- 
penter confirms this general conclusion, and points out that its 
prevalence is connected with a bottom temperature of 45°, 
which in our northern latitudes can only be attributed to the 
Gulf-stream. 
Bathybius yet requires to be considered in two other impor- 
tant relationships — the one geological and the other zoological. 
Chalk, examined microscopically, has long been known to 
abound in minute ovate organisms, known as crystalloids, asso- 
ciated with the Globigerinse and Textillarise, of which chalk 
mainly consists. I recognised the organic origin of these bodies 
in 1847, and figured one of them very imperfectly, viewed as 
an opaque object, in my memoir On some of the Microscopic 
Objects found in the Mud of the Levant;”'^ but, ignorant of 
Coccoliths, I concluded that they belonged to some minute form 
of Oolina or Lagena. More recently Mr. Sorby has subjected 
these bodies to a much more careful examination, and both he 
and Dr. Wallich have identified them with Professor Huxley’s 
Coccoliths. It now appears that both Coccoliths, Cyatholiths, 
and Coccospheres, occur fossilised in the chalk, establishing, in a 
remarkable manner, the close resemblance of the conditions 
under which the chalk-beds were formed and those existing 
along the tract of the Gulf-stream at the present da3^ Dr. 
Carpenter goes even further than this, and regards it as 
highly probable that the deposit of Globigerina-mud has been 
* Trans. Phil. Soc., Manchester,” vol. viii. fig, 71. 
